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Comparison of separated erythrocyte preparations and manual smears of bone marrow in showing micronucleus induction by clastogens and aneuploidogens in mouse.

The removal of nucleated cells from bone marrow cell suspensions by cellulose column separation and further purification in a Percoll gradient, coupled with slide preparation by a cytocentrifuge, produces uniform preparations of pure well-spread erythrocytes. The use of separated erythrocytes has been a considerable improvement in the in vivo micronucleus (MN) assay, because the optimal cell morphology and the possibility of scoring a high number of polychromatic erythrocytes (PCEs) in a short time are factors contributing to the sensitivity of the assay. As the separation procedure may selectively retain cells containing MN, a study comparing the performance of the erythrocyte fractionation technique and standard manual smear preparation was conducted in male NMRI mice treated with a single injection of two clastogens (cyclophosphamide, 25 or 50 mg/kg, or methylmethane sulfonate, 40 or 80 mg/kg) or two aneuploidogens (colchicine, 0.5 or 1 mg/kg, or vincristine sulfate, 0.05 or 0.1 mg/kg). Both the preparation methods were clearly able to detect the MN-inducing and toxic effects of the treatments. After treatment with cyclophosphamide and methylmethane sulfonate, the frequency of micronucleated PCEs (MNPCEs) was, respectively, 1.6 and 1.8 times higher in the fractionated erythrocytes than in whole bone marrow. Morphological characterization of the MN indicated that this phenomenon was due to improved identification of small micronuclei in the flat cytospun cells of the fractionated erythrocyte preparations. On the other hand, the purified erythrocyte slides contained only about half the number of MNPCEs observed in standard smears, in samples collected from mice treated with colchicine.(ABSTRACT TRUNCATED AT 250 WORDS)

Aneuploidy↗

Estrogen-induced abnormal accumulation of fat cells in the rat penis and associated loss of fertility depends upon estrogen exposure during critical period of penile development.

We previously reported that diethylstilbestrol (DES) or estradiol valerate (EV) exposure at a dose of 0.10-0.12 mg/kg, or higher, per day, on alternate days, from postnatal days 2-12, resulted in abnormal penis development and infertility (H. O. Goyal et al., 2005, J. Androl. 26, 32-43). The objective of this study was to identify a critical developmental period(s) during which EV exposure results in the observed penile abnormalities. Male pups received EV at a dose of 0.10-0.12 mg/kg on postnatal day(s) 1, 1-3, 4-6, 1-6, 7-12, 13-18, 19-24, or 25-30. Fertility was tested at 102-115 days of age and tissues were examined at 117-137 days. Both penile morphology and fertility were unaltered in rats treated with EV after 12 days of age. Conversely, except in rats treated on postnatal day 1 only, none of the males treated prior to 12 days of age sired pups, and all had abnormal penises, including varying degrees of abnormal accumulation of fat cells and loss of cavernous spaces and smooth muscle cells in the corpora cavernosa penis, which were maximal in the 1-6-day group. Also, the preputial sheath was partially released or its release was delayed, and the weight of the bulbospongiosus muscle was significantly reduced. Plasma testosterone (T) in the 1-6- and 4-6-day groups and intratesticular T in the 4-6-day group were significantly lower. The testosterone surge, characteristic of controls in the first week of life, was suppressed in the 1-3-day group. Estrogen receptor alpha mRNA expression was enhanced in the body of the penis in the 1-3-day group, but not in the 13-18-day group. Hence, EV exposure prior to 12 days of age (as short as 1-3 days postnatal), but not after 12 days of age, results in long-term abnormal penile morphology, characterized by abnormal accumulation of fat cells in the corpora cavernosa penis and, consequently, loss of fertility.

Adipocytes↗

Emergence of Fusarium oxysporum f. sp. fragariae in the Eastern United States.

Historically, Fusarium oxysporum f. sp. fragariae (Fof), the causal agent of Fusarium wilt in strawberry, has been a major problem for strawberry production in California but has been largely absent in the rest of the United States. During the growing seasons of 2023 to 2025, independent detections of Fof were made on strawberry plants exhibiting symptoms of Fusarium wilt in the eastern U.S. states of Florida, North Carolina, New York, Connecticut, and Virginia. Sixteen isolates were obtained from symptomatic plants across this region, and a subset (n = 14) were confirmed to be Fof by pathogenicity testing, morphological characterization, PCR diagnostics, and whole-genome sequencing. Specifically, these tests demonstrated that all tested isolates were virulent on susceptible (fw1) strawberry cultivars but not on resistant (FW1) cultivars, classifying them as race 1. Although all isolates tested positive with the more recently developed Fof-specific PCR assay by Burkhardt et al. (2019), many (43.75%) failed detection with the commonly used Suga et al. (2013) assay. Comparative genomics revealed that these isolates represent at least three distinct phylogenetic clades (Y1, Y2, and the putative Y10), suggesting multiple independent introductions rather than a single dissemination event. The genetic diversity of the eastern U.S. Fof populations and their likely origin from nursery stock highlight the need for more robust diagnostics, certified clean planting stock, and region-specific resistance trials to manage Fusarium wilt beyond California.

Fusarium↗

Isolation of human Leydig cell mesenchymal precursors from patients with the androgen insensitivity syndrome: testosterone production and response to human chorionic gonadotropin stimulation in culture.

Mature Leydig cells, the main source of testicular testosterone in mammals, arise from immature mesenchymal precursors through an LH-dependent differentiation process. In order to study the steroidogenic potential of these precursors, undifferentiated mesenchymal cells were obtained from the testicular interstitium of two patients with androgen insensitivity syndrome. After double digestion with collagenase and separation of the suspensions in a Percoll density gradient, the cells were cultured in Ham's F12 medium: Dulbecco's Modified Eagle Medium (1:1) supplemented with antibiotics, transferrin, insulin, hydrocortisone, and vitamin E with or without 1 IU of hCG/ml. At 11 days in culture, samples were removed for morphological characterization and determination of 3 beta-hydroxysteroid dehydrogenase activity (3 beta-HSD). Testosterone concentration was determined by RIA in the culture medium at different intervals. Cultured cells were mesenchymal in appearance, elongated in shape, with numerous processes running in different directions. No mature Leydig cells were present. In basal conditions, the percentages of 3 beta-HSD-positive cells at 11 days on patients 1 and 2 were 33% and 28%, respectively, and the testosterone concentrations in the culture media were 4.8 and 8.4 ng.10(6) cells.24 h, respectively. In cultures stimulated with hCG, there was an increase of histochemical reactivity (47% and 42% in patients 1 and 2, respectively) and in the amount of testosterone secreted (10.2 and 12.0 ng.10(6) cells, respectively). Electron microscopic studies of cultures grown in the absence of hCG demonstrated a homogenous population of poorly differentiated, fibroblastic-type mesenchymal cells.(ABSTRACT TRUNCATED AT 250 WORDS)

3-Hydroxysteroid Dehydrogenases↗

T-cell signet-ring cell proliferation in the skin simulating true histiocytic lymphoma.

We report the case of a solitary ulcerating lesion on the elbow of a 32-year-old man. Routine histopathological examination strongly suggested a histiocytic malignancy. However, electron-microscopical, enzyme-cytochemical, and immunological studies revealed that the "tumor" cells were T lymphocytes with an unusual (Leu 1+, Leu 3a+, Leu 4+, Leu 5b+, OKT4+, HLA-DR+, Ki-1+, Leu MI+) immunological phenotype and an even more uncommon morphology characterized by the development of giant multivesicular bodies giving some cells a signet-ring cell appearance, and autophagocytosis. The lesion healed spontaneously, notwithstanding its malignant histology.

Adult↗

Postmortem cerebrospinal fluid pleocytosis.

We show that postmortem cerebrospinal fluid (CSF) pleocytosis is a common event. Postmortem cerebrospinal or ventricular fluid was obtained from children and adults. The cells were counted and morphologically characterized using several histochemical markers. Infants exhibit a brisk postmortem CSF pleocytosis. Sudden infant death cases have relatively high CSF counts. Typeable cells are mononuclear and consist of approximately 60%-70% lymphocytes and 20%-40% macrophages. When postmortem duration is greater than 12 h, the cells become vacuolated and cannot be identified. The etiology of these findings requires further study.

Adolescent↗

Quantitative and qualitative assessment of morphology in sagittal synostosis: mid-sagittal vector analysis.

Consensus remains lacking regarding the optimal surgical treatment modality for sagittal synostosis. There is, however, wide agreement that objective analytical methods are required to demonstrate the characteristic morphology of the condition and to substantiate the benefits of specified surgical techniques. Simple calculated anthropomorphic indices, such as the cranial index, are commonly used but fail to provide satisfactory representation of morphology, which is far more complex than can be represented by its simple length-width ratio. Techniques to provide more comprehensive, yet practical, assessment of morphology are needed for analytic purposes. Herein, we introduce vector analysis as an objective, computed tomography (CT)-based morphometric technique for assessment of cranial morphology; this work represents the first application of the technique mid-sagittal vector analysis (MSVA). MSVA is a single plane application that was devised to address dysmorphology in sagittal synostosis. It was our hypothesis that MSVA would quantitatively and qualitatively depict preoperative morphology and postoperative correction in specific regions. Sixteen patients undergoing cranial reshaping surgery for sagittal synostosis were included in the study. All patients underwent routine preoperative and 1 year postoperative CT scans, from which the MSVA was derived. MSVA is a radial vector analysis in which distances to the cranial surface are measured from a single reference point origin in the sagittal plane. Preoperative morphology, characterized by respective vectors, was analyzed in three regions: the frontal, vertex, and occipital regions. Comparison with postoperative paired data was conducted for each patient. The analysis of postoperative change demonstrated (1) decrease in prominence in the frontal and occipital regions, (2) increase in height and forward translation of the vertex, and (3) ability to distinguish and qualify frontal versus occipital bossing and correction thereof. We conclude that the longitudinal differences associated with scaphocephaly are well characterized and differentiated by MSVA. Quantitative and qualitative assessment identifies three relevant regions affected by the condition and its treatment: the frontal, vertex, and occipital regions. The transverse dimension is not addressed in this single plane analysis; a more comprehensive application will require additional planes of analysis and the development of a normative database.

Cephalometry↗

Cemented femoral component surface finish mechanics.

A cemented femoral component's surface finish may influence implant function through variations in cement adhesion and abrasion properties. Morphologic characterization of historic and current femoral hip prosthesis surface finishes show greater than x 20 range in implant roughness. Early implants typically had relatively smooth surfaces, whereas many of the more recent implants have rougher surface finishes. Smoother implant surfaces have lower cement-metal interface fixation strength, whereas rougher surfaces have greater fixation strength. With interface motion, the smoother surfaces are less abrasive of bone cement, whereas rougher implant surfaces are more abrasive. Because of enhanced bone cement attachment, rougher implant surfaces may have a lower probability of interface motion, while at the same time, a higher debris generation consequence if motion occurs. In contrast, smoother implant surfaces may have a higher probability of interface motion with a lower debris generating consequence of that motion. The prolonged use of cemented total hip replacement may be approached by either extending the duration of implant function after cement-metal interface loosening with smooth surfaced implants or, in contrast, by extending the duration of cement-metal interface adhesion with rougher surfaced implants.

Arthroplasty, Replacement, Hip↗

Renewal of the rabbit corneal epithelium as investigated by autoradiography after intravitreal injection of 3H-thymidine.

PURPOSE: To evaluate the renewal time of the rabbit corneal epithelium and to verify whether there are differences in the rate of renewal related to the topography of the cornea. METHODS: After the intravitreal injection of 20 microBq/eye of 3H-thymidine (3H-TdR), the rabbits were killed at variable survival-time intervals (3 hours to 90 days), and their corneas were processed for autoradiography on paraffin and 0.75-microm-thick Epon sections. The frequency of labeled nuclei, per each linear millimeter of epithelium, was estimated on paraffin sections of the whole length of the cornea of rabbits killed 6 hours after injection. The activity of unbound 3H-TdR was measured in the vitreous and aqueous humor. RESULTS: The incorporation of 3H-TdR into newly synthesized DNA ceased between 1 and 2 days after the intravitreal injection. At the shortest time intervals (3 hours to 1 day), the overwhelming majority of the labeled nuclei were located in the basal stratum of the stratified squamous epithelium. Cells of the wing stratum were labeled from 3 days onward. At 14 days, labeled nuclei were visualized only in the inner portion of the surface stratum, whereas their outermost layers were labeled only at 21 days and later. Lightly labeled nuclei could still be detected in the epithelium < or = 90 days after injection. The counts of labeled nuclei did not show significant differences in their frequencies between the periphery and the center of the cornea. The existence of vascularization at the periphery of the corneal stroma and the lack of a conspicuous Bowman's layer made it difficult to characterize morphologically the rabbit limbus with the light microscope. CONCLUSION: It takes >14 days for a daughter cell to migrate from the basal stratum to the outermost layer of the epithelium. Labeled daughter cells were detected < or = 90 days in several layers of the corneal epithelium. Therefore it takes >2 weeks for the complete renewal of the epithelium. Our data suggest that the proliferative capability of the centrally located basal cells is enough to guarantee the renewal of the corneal epithelium under physiologic conditions.

Animals↗

Establishment of a human lacrimal gland epithelial culture system with in vivo mimicry and its substrate modulation.

PURPOSE AND METHODS: Viable single human lacrimal gland (LG) epithelial cells were obtained by serial incubation in chelating and enzymatic solutions. These cells were evaluated for outgrowth in growth factor-enriched medium using the following culture substrates: Matrigel type I collagen gel with or without fibroblasts, and plastic. Each epithelial outgrowth was characterized morphologically and immunohistochemically, and their growth and viability were examined by bromodeoxyuridine (BrdU) labeling and a quantitative cell viability assay. Synthesized proteins were evaluated by enzyme-linked immunosorbent assay (ELISA), sodium dodecyl sulfate polyacrylamide gradient gels, and 14C-amino acid incorporation. RESULTS: LG epithelial cells plated on Matrigel formed clusters with central cavities that contained lactoferrin, mimicking acinar complexes in vivo. Cells plated on Matrigel containing fibroblasts formed tubuloacinar structures and resembled the human LG in vivo. Cells plated on collagen gel or collagen gel containing fibroblasts formed islands or a monolayer, and lactoferrin was detected in incomplete cavities of epithelia on the latter substrate. Epithelial cells plated on plastic formed a monolayer, and cellular expression of lactoferrin was weak and sporadic. Cellular release of lactoferrin measured by ELISA supported the results of immunohistochemistry. Significant differences in proliferative rate were noted between substrates; cells grown on plastic had the highest proliferative rate, whereas cells grown on Matrigel had the lowest rate. CONCLUSION: Culture substrates modulate LG epithelial cell morphology, proliferative rate, and production of the tear protein lactoferrin. Matrigel promotes acinar differentiation to a greater extent than collagen gel and plastic. Incorporation of fibroblasts in substrates promotes ductal differentiation.

Adolescent↗

Glaucomatous neurodegeneration and the concept of neuroprotection.

Glaucomatous neurodegeneration is a progressive pathological affair morphologically characterized by RGC death resulting in functional visual deterioration. Although a variety of primary insults ranging from mechanical trauma to ischemia to genetic susceptibility can initiate disease onset, apparently loss of trophic support and excitotoxin release remain the common themes responsible for neuronal damage and eventual cell death by apoptosis. The spread of this damage is perpetuated by secondary degeneration that allows directly injured neurons to release noxious and degenerative substances into the surrounding cells. Neuroprotection is a collective therapeutic approach the aim of which is to provide resilience to such neurons in an effort to prevent or delay progressive neuronal degeneration. At present, definitive neuroprotective therapy remains unachieved despite a variety of approaches having been defined and intensely pursued. However, the evolution in our understanding of glaucoma continues to offer reason for optimism. To this end, we remain unreservedly hopeful in the labor and committed work of dedicated investigators. We are all indebted to them.

Apoptosis↗

Antibacterial properties of lansoprazole alone and in combination with antimicrobial agents against Helicobacter pylori.

The activities of various types of anti-ulcer agents against Helicobacter pylori (Hp) strains were determined using an agar dilution method. Among the compounds tested, proton pump inhibitors were found to exhibit significant activity against this organism. The activity of lansoprazole was four times more potent than that of omeprazole and bismuth subsalicylate, with MICs ranging from 1.56 to 25 micrograms/ml. Exposure of Hp to lansoprazole led to extensive loss of viability and suppression of virulence factors such as motility, adhesiveness to epithelial cells, and urease activity. Lansoprazole produced aberrant bacterial morphology characterized by elongation and constriction of the cells and collapse of cell surface structures. The combination of lansoprazole with antimicrobial agents such as penicillins, cephalosporins, macrolides, tetracyclines, aminoglycosides, quinolones, and metronidazole produced an additive or synergistic growth inhibition of Hp.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Single-cell characterization of endothelin system gene expression in the cerebellum in situ.

To evaluate the expression of components of the endothelin (ET) system in single Purkinje neurons and Bergmann glial cells in situ, patch-clamp recording was combined with a multiplex RT-PCR approach. Cerebellar slices were rapidly isolated from 20- to 28-day-old mice. Cells were characterized morphologically and electrophysiologically and cell contents were aspirated and immediately reverse-transcribed. The cDNA was used as a template in a multiplex PCR reaction containing primers specific for ET-1, ET-2, and ET-3, ET-converting enzyme 1 (ECE-1) and ECE-2, and ETA and ETB receptors. The resulting PCR products were used as templates in a second PCR reaction containing only one pair of nested primers. Specific single bands were obtained from positive cells, which was confirmed by DNA sequencing of the PCR products. Of the 25 Purkinje neurons assayed, 84% were positive for ECE-1 mRNA and 68% for ECE-2 mRNA. No ET and ETA receptor mRNAs were detected, and only one cell was positive for ETB receptor mRNA. In Bergmann glial cells, ETB receptor mRNA was predominant. A total of 68% of the 25 cells assayed were positive. Sixteen percent were positive for ETA receptor mRNA, 8% for ECE-1 mRNA, and 12% for ECE-2 mRNA. Again, no ET mRNAs were detected. These results confirm the role of the ETB receptor in Bergmann glial cells and provide evidence for expression of ECE-1 and ECE-2 in Purkinje neurons.

Animals↗

T cell functional defect associated with thymid epithelial cell injury induced by a graft-versus-host reaction.

The injection of parental strain cells into adrenalectomized (CBA x A)F1 mice induced a graft-versus-host (GVH) reaction which was morphologically characterized by thymus epithelial cell injury but not stress-related thymic involution. Thymocytes from mice undergoing a GVH reaction were studied for their ability to reconstitute allograft reactivity in thymectomized, irradiated, bone marrow reconstituted (ATxBM) (CBA x A)F1 mice. Thymocytes of mice experiencing a GVH reaction were theta-positive during the course of the reaction, however, by 40 days after GVH induction these thymocytes were unable to reconstitute allograft reactivity to H-2-incompatible skin grafts. It is proposed that GVH-induced thymic epithelial cell injury prevents or arrests normal T cell differentiation, resulting in a population of thymocytes which lack complete functional capability.

Animals↗

Age-associated changes in histology and gene-expression profile in the rat ventral prostate.

The incidence of prostate diseases rises dramatically with age in men, yet little is understood of the mechanisms underlying prostatic senescence and its contribution to disease development in the gland. In Noble rats, aging of the ventral prostate (VP) is characterized morphologically by widespread atrophy of acini, increased accumulation of concretions in glandular lumen, infiltration of inflammatory cells, and focal epithelial atypia. We used a cDNA microarray containing 2388 known transcripts, together with the Tyramide Amplification System and t statistics, to identify differentially expressed genes in the VPs of young (3 months old) and old (16 months old) rats. A total of 78 VP genes were found to be differentially expressed by the two groups; in old rats, 65 VP genes (83%) showed reduced expression and 13 genes (17%) showed increased expression compared with young animals. The age-dependent underexpressed genes fell into several functional clusters: those involved in amino-acid metabolism, protein synthesis, protein secretion and degradation, vesicle/membrane trafficking, energy metabolism, signal transduction, spermidine and spermine syntheses, and cellular defense against stress. The overexpressed genes included iduronate 2-sulfatase, HLA class I locus C heavy chain, membrane cofactor protein of the complement system, TRPM-2, cadherin-associated protein-related, and X-CGD. Post hoc analyses confirmed a progressive decline in the expression of ribophorin II and BiP and a gradual increase in the expression of TRPM-2 in rat VPs as animals aged from 3 to 19 months old. In conclusion, the observed widespread declines in expression of genes involved in protein synthesis, protein fidelity maintenance, anabolism, growth inhibition, and energy metabolism, together with increased expression of genes implicated in cell survival in the VPs of senescent rats, may help explain the susceptibility of the prostates of elderly men to development of disease.

Age Factors↗

Nonsynostotic occipital plagiocephaly: radiographic diagnosis of the "sticky suture".

BACKGROUND: While the clinical differences between nonsynostotic occipital plagiocephaly and lambdoid craniosynostosis have been described, the radiographic differentiation between the two remains obscure. The aim of this study was to characterize morphological differences in the lambdoid suture between nonsynostotic occipital plagiocephaly and lambdoid craniosynostosis. METHODS: Computed tomography scans of children clinically diagnosed with nonsynostotic occipital plagiocephaly (n = 26) were compared with computed tomography scans from children diagnosed with lambdoid craniosynostosis (n = 7). Suture and cranial morphology, ear position, and endocranial base angles were qualitatively and quantitatively compared. RESULTS: Nonsynostotic occipital plagiocephaly sutures demonstrated areas of focal fusion (25 percent), endocranial ridging (78 percent), narrowing (59 percent), sclerosis (19 percent), and changes from overlapping to end-to-end orientation (100 percent). No sutures demonstrated ectocranial ridging. All cases of nonsynostotic occipital plagiocephaly presented with ipsilateral occipital flattening, 85 percent with ipsilateral frontal, and 95 percent with contralateral occipital bossing producing parallelogram morphology. In contrast, a greater frequency of sutures in lambdoid craniosynostosis patients demonstrated nearly complete obliteration (p < 0.001) with ectocranial ridging (p < 0.001); significantly more of these patients presented with ipsilateral occipital flattening with compensatory ipsilateral mastoid (p < 0.001) and contralateral parietal (p < 0.01) bossing, producing a trapezoid morphology. Sutures from nonsynostotic occipital plagiocephaly patients showed endocranial ridging, focal fusions, and narrowing, previously reported as lambdoid craniosynostosis. CONCLUSIONS: In contradiction to previous reports, lambdoid craniosynostosis is not radiographically unique among suture fusions. This work establishes the radiographic diagnosis of nonsynostotic occipital plagiocephaly.

Child, Preschool↗

Benign mixed epithelial and stromal tumor of the kidney: imaging findings.

Three cases of mixed epithelial and stromal tumor of the kidney with their imaging findings are described; these cases have not been reported previously in the radiology literature. This benign tumor contains epithelial and spindle cell stromal components and arises exclusively in adult women. It is characterized morphologically by a solid and cystic nature with delayed enhancement.

Adult↗

Hyperaggregating effect of hydroxyethyl starch components and University of Wisconsin solution on human red blood cells: a risk of impaired graft perfusion in organ procurement?

BACKGROUND: The standard preservation solution used during organ procurement and preservation of most organs is the University of Wisconsin (UW) solution. Despite its superiority over other cold storage solutions, the inclusion of hydroxyethyl starch (HES) as one of the components of the UW solution has been both advocated and denied. This study determined whether HES had any effect on red blood cell (RBC) aggregability and correlated aggregation parameters with HES molecular weight. METHODS: Human RBC aggregability and deformability were investigated in vitro, at 4 degrees C, with a laser-assisted optical rotation cell analyzer. The study of RBC aggregation in a binary HES-HES system gave an indication about the nature of HES-RBCs interactions. Bright field microscopy and atomic force microscopy were used to morphologically characterize the aggregates size and form. RESULTS: High molecular weight HES and UW solution had a potent hyperaggregating effect; low molecular weight HES had a hypoaggregating effect on RBC. RBC aggregates were of large size and their resistance to dissociation by flow-induced shear stress was high. CONCLUSION: The authors' in vitro experiments conclusively showed that the physiologic function of RBCs to form aggregates is significantly affected in the presence of HES. The use of high molecular weight HES in UW solution accounts for extended and accelerated aggregation of erythrocytes that may result in stasis of blood and incomplete washout of donor organs before transplantation.

Adenosine↗